Prokofiev left Russia for Paris during the revolution, but then returned to Russia under Stalin, where he stayed. He died the same day as Stalin, but because the streets were mobbed due to the dictator's death, it took 3 days before they could move Prokofiev's body out of the house. It must have been a tough 3 days for the people trapped with him in the house.
Stravinsky left Ukraine for Switzerland when World War I broke out, and he never returned to Russia again except for a concert tour in 1962.